close all
clear all
clc

xa=linspace(-2,2,50);
ya=linspace(-1,1,25);

[Y,X] = meshgrid(ya,xa);

D=X.^2+Y.^2;
pcolor(xa,ya,D');
colormap('jet');
% shading faceted;
% shading flat;
shading interp;
axis equal tight;

